Media Technology & Innovation

Optimised Software H265/HEVC Encoder for UHDTV

With the rapidly growing interest and demand for Ultra High Definition Television (UHDTV) services, the developments in video compression technologies have key challenges to face. The H.265/HEVC standard is considered as the coding technology of choice due to its enhanced compression efficiency, to help cope with the significantly increased data rates in UHDTV signals.

However, this superior compression performance of HEVC has come at the expense of increased computational complexity, which is estimated at up to 4 times that of its predecessor H.264/AVC. Thus, the development of real-time H.265/HEVC encoders for UHDTV, particularly the software implementations that can run on general purpose hardware is an ongoing challenge.

BBC Research & Development has been leading an Innovate UK co-funded collaborative project called THIRA to address this challenge. THIRA addresses the storage and delivery of ultra-high definition material in UHDTV services. The project studied the potential of each coding tool standardised by HEVC over a large set of UHD test material representative of television broadcasting content. This led to the design of a number of techniques to speed up the HEVC coding process with minimal impact on the compression efficiency. As a result, the THIRA project has created an optimised software HEVC encoder which integrates the tools by the project and also implements the desired features of a practical encoder, such as parallel processing, reduced memory footprint, rate control, shot change detection and adaptive adjustment of the GOP structure.

Coming towards the end of the THIRA project, at IBC 2015 in Amsterdam, BBC R&D will demonstrate the technology developed by the project, will present the main compression results with enhanced coding speed, and key features of the codec.